Fixing issues #103 and #127 with bytes and bigbytes

[pjakubik]

• Bytes returns 32 MB for 31450000 bytes instead of 31 MB #103 double rounding edge case returns wrong value
• Don't output 1000 kB for 1.0 MB #127 outputting 1000 kB instead of 1.0 MB for some values
• unit tests updated and/or added for above fixes

Fix also speeds up the float and int formatting so that after adding extra logic to fix edge cases, humanateBytes and humanateBigBytes are faster than they were before.

More details on #103 fix

Here is what the code did with the specific issue reported with humanizing 31450000

1. Calculate that this should be 31.45 MB
2. Multiply 31.45 by 10 and add 0.5 -> 315.0
3. Floor of 315.0 then divide by 10 -> 31.5
4. Tell Sprintf to format 31.5 with no decimals -> Sprintf rounds to 32
5. Return "32 MB" instead of expected "31 MB"

Fix now rounds differently depending on if value being rounded is >= 10 or <10 so that after rounding, Sprintf won't round again.